Abstract
To efficiently plan species conservation, we must first understand species-specific movement and habitat preferences. This is particularly true of biphasic amphibians, because they require high-quality habitat within two distinct habitat types and individuals need to be able to move between these habitats to complete their life cycle. Movement and microhabitat use are difficult to study in small-bodied amphibians, especially those that are fossorial. To overcome these challenges and illuminate the ecology of an imperiled subspecies, we applied drift fence and fluorescent powder tracking methods to reveal the initial movement pathways and terrestrial microhabitat preferences of recently metamorphosed Santa Cruz Long-toed Salamanders (SCLTS; Ambystoma macrodactylum croceum). Drift fence data indicated that SCLTS juveniles emerge nonrandomly from pond basins. At the two breeding sites with the most distinct habitat transitions, this nonrandom pattern was negatively correlated with distance to canopy cover. By contrast, juveniles of an imperiled and sympatric congener, the California Tiger Salamander (Ambystoma californiense), emerged with a positive correlation with distance to canopy cover, indicating niche partitioning of terrestrial habitats. Powder tracking of juvenile SCLTS also demonstrated nonrandom movements oriented toward areas with more trees, higher soil moisture, and greater canopy cover. The longest trail we followed was 72 m, a record for published powder tracking of Ambystoma. These findings emphasize the importance of restoring closed canopy habitat that retains soil moisture in close proximity to the limited breeding sites for this imperiled taxon.